Off-set nut runner with open-end access and socket-like drive capability

ABSTRACT

A nut or bolt head driver employing a drive belt of flat surfaced links carried around a multi-faced rotatable driving member in a housing and extending from one housing end in loop fashion around an arcuate tension plate fixed to the housing end. Belt tension adjusting means confine a nut or bolt to be driven between nut face-engaging ones of successive belt links and apices of the nut to be driven which maintain sliding point contact on the tension plate surface. At least one link of the belt is selectively disengageable to permit open-end access to a nut or bolt head with subsequent belt engagement and tension adjustment, whereupon the nut or bolt head may be driven in the fashion of a box wrench or socket drive upon laterally offset drive torque being imparted to the belt driving member.

United States Patent [1 1 [111 3,913,428

Brunson Oct. 21, 1975 OFF-SET NUT RUNNER WITII OPEN-END Primary Examiner-James L. Jones, Jr.

ACCESS AND SOCKET-LIKE DRIVE CAPABILITY Attorney, Agent, or Firm-Warren H. Kintzinger [57] ABSTRACT A nut or bolt head driver employing a drive belt of flat surfaced links carried around a multi-faced rotatable driving member in a housing and extending from one housing end in loop fashion around an arcuate tension plate fixed to the housing end. Belt tension adjusting means confine a nut or bolt to be driven between nut face-engaging ones of successive belt links and apices of the nut to be driven which maintain sliding point contact on the tension plate surface. At least one link of the belt is selectively disengageable to permit openend access to a nut or bolt head with subsequent belt engagement and tension adjustment, whereupon the nut or bolt head may be driven in the fashion of a box wrench or socket drive upon laterally offset drive torque being imparted to the belt driving member.

10 Claims, 5 Drawing Figures US. Patent Oct. 21, 1975 FIG. 2

FIG. 3

FIG. 4

OFF -SET NUT RUNNER WITII OPEN-END ACCESS AND SOCKET-LIKE DRIVE CAPABILITY This invention relates in general to wrenches and, in particular, to a nut-running device having a lateral offset socket-like drive capability and provision for openend access to a nut to be driven.

Socket wrench drive devices are often cumbersome, ineffective, and sometimes impossible to use for driving nuts in inaccessible and/or confined quarters. For this reason, devices have been devised to provide a tool with lateral offset capability for use in engaging and driving nuts in confined quarters. Known devices include a driving member in combination with a laterally offset nut-engaging driven member, whereby a wrench or socket driver may be used to torque the driving (accessible) member, and thus drive be imparted to the laterally offset driven member which engages the nut to be driven. The applied drive is imparted in offset fashion to the driven member by means of various mechanical arrangements, including the well-known chain and sprocket means, interconnecting gear drive train, cam and cam-follower arrangements, etc.

Known devices of this type, as typified for example in US. Pat. Nos. 2,817,256; 3,618,430; 3,564,953; and 3,714,852, provide a driven member, which engages the nut to be driven, that necessarily engages the nut in the manner of a box wrench, or socket; that is, they are effective in driving inaccessible nuts only when sufficient end clearance is available to permit placing the driven member of the device over the nut and into driving engagement therewith.

Devices of the above-referenced and-described type function generally as a lateral offset drive means for a socket wrench and do not permit driving engagements with nuts when clearance does not permit use of socket drives.

It is therefore a principal object of this invention to provide a nut driver having the speed advantage of a socket wrench, and having lateral offset drive capability, with provision for operably' engaging a nut to be driven in a location which would normally preclude use of box-end wrenches or sockets, and which would render the use of open-end wrenches inefficient.

Another object is to provide a nut-running device with lateral offset drive capability which readily may be engaged with a nut or bolt head normally requiring an open-end engagement type of tool, and thereafter be rendered operative to rapidly drive the nut in the efficient and expedious manner characteristic of socket nut drivers.

A further object for such a nut-runner is to permit efficient driving engagement of the device with nuts or boltheads having a range of dimensions across the flats thereof.

Features of this invention useful in accomplishing the above objects include, in a nut-runner device having lateral offset drive capability and open-end nut and bolthead access capability, a selectively linkable' drive bolt structure with belt-linked lengths generally defined by the length of the flats of a nut or bolthead to be driven. The linked belt is looped around a driving member having a plurality of flat sides, the dimensions of which likewise correspond generally to that of the nut or bolthead to be driven. The belt structure is carried in loop fashion over a nut or bolthead to be driven, and belt tension adjusting means provides for loading the nut or bolthead against a fixed, arcuate tension plate. The drive belt link flats conformingly engage plural adjacent flats of the nut or bolthead to be driven, while at least two adjacent apices of the nut or bolthead maintain sliding point contact with the arcuate tension plate surface. Chain tension adjustment permits a stabilized driving engagement between engaged belt link surfaces and nut or bolthead flats, while permitting efficient transfer of driving torque imparted to the laterally offset driving member by a conventional wrench or socket drive tool. The drive belt is provided with at least one selectively disengageable link whereby disengaged belt ends may be looped around a nut in an environment providing insufficient or non-existent end access space, and then re-engaged to permit that nut or bolt to be rapidly run in socket drive fashion.

A specific embodiment representing what is presently regarded as the best mode of carrying out the invention is illustrated in the accompanying drawing, wherein:

FIG. 1 represents a perspective view of a nut-runner, with drive belt disengaged to permit open-end-like access to a nut or bolt to be driven;

FIG. 2, a top cut-away and partially sectioned view taken along line 22 of FIG. 1, showing driving engagement between the nut-runner and a nut to be driven;

FIG. 3, a side-elevation cut-away and partially sectioned view of the nut-runner taken along line 3-of FIG. 1;

FIG. 4, a top view of a removable cover member as depicted in FIGS. 1 and 3; and,

FIG. 5, a perspective view of a drive belt channelguide member as depicted in FIGS. 2 and 3.

REFERRING TO THE DRAWING side walls and extend the length of body housing 10 to form an enclosure for the drive mechanism to be'described. As best depicted in FIG. 4, top cover 11 may be formed with an elongated cut-out slot 12 to provide sliding clearance for the shaft of a belt driving member which is rotatable to impart drive to belt 13 by means of external accessed bolthead 14. As will be further described, the driving member is longitudinally translatable with respect to the body housing 10 by means of a belt tension adjustment. Rotation of a tension adjustment screw handle 15 loads the U-shaped frame member 16 against the rear wall of body housing 10 for this purpose. The drive belt 13 of FIG. 1 is depicted as extending from body housing 10, between the respective side walls of body housing 10 and the side extremes of an arcuate tension plate 17. Depicted belt end links 18 and 19 are provided with appropriate selective engagement means, such as respective hood and pin, or pin and socket means, to permit the belt 13 to readily be engaged or disengaged at this point. The devices, as depicted in FIG. 1, might then be employed, in open-endaccess fashion, to engage a nut or bolthead to be driven by carrying the belt ends around the nut or bolthead and completing the belt link engagement, then tightening the chain by means of adjusting 15 to hold the nut or bolthead in confined engagement between belt l3 and tension plate 17.

As best depicted in FIG. 2, drive belt 13 is slidably confined within the body and cover assembly by means of guide channels. Side guide channels are formed by means of internal side wall members 20 and 21 affixed to and extending upwardly from the bottom 22 of body housing 10. Wall members 20 and 21 extend from the transverse extremes of arcuate tension plate 17, in parallel with the respective side walls of housing to provide a confining channel for chain 13 of sufficient width to permit chain travel and yet prevent the chain from flexing in the channels so as to prevent chain collapse within the channel confines if the device is held upwardly with belt link disengagement.

As depicted in FIGS. 2 and 3, the belt drive assembly is comprised of a hexagonal member 22 which might comprise a hex nut member threaded on the shaft 23 of a bolt which is rotatably received through throughholes in the top and bottom surfaces of U-shaped bracket member 16, and passes through an elongated through-slot 24 formed in the bottom plate of body member 10. The hexagonal member 22, carried on bolt 23, might be constrained from rotation, once positioned on bolt 23, by pin means 25.

U-shaped bracket member 16 is dimensioned for a sliding fit with respect to body housing 10, and by means of tension adjusting screw 15, threadedly re ceived in the end of U-shaped bracket 16, and extended into a socket-like depression 26 in the end of body housing 10. U-shaped bracket member 16 may be translated rearwardly with respect to body housing 10, thus tightening chain 13 to impart loaded engagement of a nut 27 between drive belt 13 and tension plate 17.

The belt drive assembly additionally comprises a generally arcuate chain guide channel member 28 which translates with respect to body housing 10, upon the belt tension being adjusted, and forms an outer side wall to confine belt 13 with respect to the periphery of hexagonal driving member 22, and thus prevents the belt, upon link disengagement, from slipping into the confines of the body housing.

Belt guide channel member 28 must therefore maintain a fixed, spaced relationship with respect to driving member 22. For ease in assembly, belt guide channel member 28 might thencomprise, as best illustrated in FIG. 5, respective top and bottom plate members 29 and 30 formed with side flats 28b and 28c and simicircular ends 28a, joined by a side wall. Through-holes 31 and 32 as in the respective top and bottom plate members may rotatably receive the shank of drive bolt 23, with the axes of the through-holes 31 and 32 defining the radius of curvature of the semicircular ends 28a. As depicted in FIG. 3, channel guide 28 may be received on drive bolt 23 so as to be translatable therewith upon a chain tension adjustment being made, with the flat sides 28b and 280 thereof in sliding engagement with the respective inner surfaces of the side walls of body member 10, such that the channel member 28 is constrained from rotation about the axis of drive bolt 23, and thus with respect to the body housing 10.

The afore-described cover plate 11, by means of the slot 12 formed therein, may be, as depicted in FIG. 3, slid into place and affixed by means of a screw fastener 33 passed through hole 34 in the cover into threaded engagement with a dog or bracket member 35 affixed to and extending upwardly from, the bottom plate of body member 10. i

In operation, a nut to be run is placed in confined, driven engagement with the drive belt by easing the tension adjustment to permit slipping the chain and tension plate over the flats of the nut, with the chain intact if end clearance so permits; or, alternatively, by easing tension, disengaging the belt links, and placing the belt ends over the nut with subsequent belt link engagement. The tension adjustment may then be adjusted to tighten the chain and urge the nut to be driven against the tension plate, with the flats of plural adjacent belt links held in conforming, driving engagement with adjacent flats of the nut. Two or more apices of the driven nut are loaded into sliding point contact on the arcuate tension plate, maintaining a stable driving engagement between successive belt link flats and those of the nut with which they conformingly engage. Once chain tension is set for driving engagement, the driving member may be rotated by applying a standard wrench or socket drive means to either the drive bolthead 14 or drive socket recess 36 formed in the drive bolthead. Belt'tension may readily be adjusted to maintain a stable driving engagement with the nut to be run. Frictional retarding force between the tension plate and the engaging ones of the driven nut head apices may be minimized by constructing the tension plate from a material having appropriate lubricity and hardness characteristics.

The nut-runner herein described is useful in running nuts or driving boltheads which have a plurality of faces the lengths of which are substantially equal to the length of the links that comprise the drive belt.

A variety of belt link face configurations might be employed as well as various belt linkage means, and, further, various known means for facilitating selective disengagement of the belt linkage might be employed. Thus, whereas this invention is herein illustrated and described with respect to a single embodiment thereof, it should be realized that various changes may be made without departing from essential contributions to the art made by the teachings hereof.

I claim:

1. A nut driving tool with lateral offset drive capability comprising, a body housing; a drive belt means comprised of contiguous flat-surfaced links; belt driving means comprising a driving member rotatable with respect to said body housing, and formed with a plurality of contiguous flat edge faces; said drive belt means being carried around said driving member and extending in loop fashion externally of one end of said body housing; a concave arcuate tension plate means affixed to said body housing at said one end thereof, with said drive belt extending between transverse extremes of said tension plate means and respective side walls of said body housing; means for selectively translating said driving member to establish, the longitudinal displacement between said tension plate means and said driving member; and means external of said body housing and communicating with said driving means by which rotary motion may be imparted to said driving member.

2. The nut driving tool of claim 1, wherein the lengths of said driving member flat edge faces are substantially equal the lengths of said drive belt links.

of the flats of a nut to be driven by said nut driving tool.

5. The nut driving tool of claim 3, wherein said arcuate tension plate means is formed with a radius substantially equal that defining the respective apices of a nut to be confined between said tension plate and the externally extending portion of said drive belt means.

6. The nut driving tool of claim 5, wherein said arcuate tension plate means is symmetrically disposed with respect to the longitudinal axis of said body housing and extends over an arc less than 180 and greater than 60.

7. The nut driving tool of claim 6, wherein said arc is substantially equal to and less than 120.

8. The nut driving tool of claim 6, wherein said body housing is formed with internal channel-defining side wall members extending from the transverse extremes of said arcuate tension plate means toward said driving member, and disposed substantially parallel to respective side walls of said body housing, said drive belt means being confined between said side wall members and the respective body member side walls.

9. The nut driving tool of claim 8, comprising an arcuate wall member within said body housing and extending contiguously between said side wall members and concentrically about the radial extremes of said driving member, said drive belt means being confinably received between said driving member and said arcuate wall member.

10. The nut driving too] of claim 9, comprising mounting means for said arcuate wall member whereby said arcuate wall member is longitudinally displaceable with respect to said body housing in concert with said driving means, and means for constraining said arcuate wall members from rotation with respect to said body housing. 

1. A nut driving tool with lateral offset drive capability comprising, a body housing; a drive belt means comprised of contiguous flat-surfaced links; belt driving means comprising a driving member rotatable with respect to said body housing, and formed with a plurality of contiguous flat edge faces; said drive belt means being carried around said driving member and extending in loop fashion externally of one end of said body housing; a concave arcuate tension plate means affixed to said body housing at said one end thereof, with said drive belt extending between transverse extremes of said tension plate means and respective side walls of said body housing; means for selectively translating said driving member to establish the longitudinal displacement between said tension plate means and said driving member; and means external of said body housing and communicating with said driving means by which rotary motion may be imparted to said driving member.
 2. The nut driving tool of claim 1, wherein the lengths of said driving member flat edge faces are substantially equal the lengths of said drive belt links.
 3. The nut driving tool of claim 2, wherein said drive belt means is comprised with means for selectively disengaging at least one link thereof.
 4. The nut driving tool of claim 3, wherein said driving member has a dimension along the respective side flats thereof, corresponding substantially to the lengths of the flats of a nut to be driven by said nut driving tool.
 5. The nut driving tool of claim 3, wherein said arcuate tension plate means is formed with a radius substantially equal that defining the respective apices of a nut to be confined between said tension plate and the externally extending portion of said drive belt means.
 6. The nut driving tool of claim 5, wherein said arcuate tension plate means is symmetrically disposed with respect to the longitudinal axis of said body housing and extends over an arc less than 180* and greater than 60*.
 7. The nut driving tool of claim 6, wherein said arc is substantially equal to and less than 120*.
 8. The nut driving tool of claim 6, wherein said body housing is formed with internal channel-defining side wall members extending from the transverse extremes of said arcuate tension plate means toward said driving member, and disposed substantially parallel to respective side walls of said body housing, said drive belt means being confined between said sIde wall members and the respective body member side walls.
 9. The nut driving tool of claim 8, comprising an arcuate wall member within said body housing and extending contiguously between said side wall members and concentrically about the radial extremes of said driving member, said drive belt means being confinably received between said driving member and said arcuate wall member.
 10. The nut driving tool of claim 9, comprising mounting means for said arcuate wall member whereby said arcuate wall member is longitudinally displaceable with respect to said body housing in concert with said driving means, and means for constraining said arcuate wall members from rotation with respect to said body housing. 